I'd like battery voltage, oil and or coolant temperature and oil pressure. It seems the least expensive way to monitor most of these parameters is to use an OBD2 bluetooth module with a smart phone and an application like Torque or Torque Pro and a smart phone or tablet.

Does anyone know if this combination will allow you to monitor oil pressure?
Suggestions for an ap better than Torque Pro also which OBD2 blue tooth module do you suggest. They are all over the park with costs from $10 to $100.